Rotary clutch



Aug. 19, 1941.

F. A. HOWARD ROTARY CLUTCH a Sheets-Sheet 1 Original Filed Jan. 3, 1953 Aug. 19, 1941. 'F, A. HOWARD 7 2,253,299

ROTARY CLUTCH Original Fild Jan. 3, 1933 e Sheets-Sheet 2 r IIIIIIIIIIIMV 1 Aug. 19, 1941.

F. A. HOWARD ROTARY CLUTCH Original Filed Jan. a, 1553s a Sheets-Sheet 3 NM 1 UN m Q wwQ Aug. 19, 1941. F. A. HOWARD 2,253,299

. ROTARY CLUTCH Original Filed Jan. 3, 1933 6 Sheets-Sheet 4 Aug. 19, 1941} F, A AR I 2,253,299

ROTARY CLUTCH Original Filed Jan. 3, 1933 e Sheets-Sheet 5 a l S 1;??? H) Aug. 19, 1941. 1-" A. HOWARD 2,253,299

ROTARY cmm'cn Original Filed Jam. 3, 1933 6 Sheets-Sheet 6 1 v 00 Jy/l wrlirdf aa V lllll l l lllr c Q I v N w W Patented Aug. 19, 1941 2,253,299 ROTARY CLUTCH Frank A. Howard, Elizabeth, N. J.

Original application January 3, 1933, Serial No. 650,018. Divided and this application April 2,

I 1938, Serial No. 199,551

6 Claims. Cl. 192-58) This invention relates to a propulsive unit which includes an internal combustion engine and a liquid coupling for transmitting the power of the engine to the load .and means for circulating lubricating liquid from the engine through the coupling where it is cooled and then back to the engine.

The invention relates also to a fluid displacement machine or clutch in which positive displacement o-f a working fluid against pressure is effected by power applied to the driving of the machine. While the motion of the displacing member is one of rotation, there is a supplementary reciprocating motion essential to the operation.

In all such positive fluid displacement machines the fundamental kinematic problem is that of expanding and contracting the working chambers and mechanically coupling the moving walls of these chambers to those portions of the machine which are intended to transmit power to or from them. In the rotary clutch the power is transmitted directly to or from a casing by a moving chamber wall in the form of a rotating ring called the rotor J'ournalled on the crank pin. This moving wall is supplemented by partitioned walls calledvanes which also move, but only by reciproeatingin their own planes, and therefore against frictional resistance alone.

In the kinematic design the positive motion of the rotor is that of an eccentric strap with an infinitely long connection rod, but in addition to this positive motion, it is free to slip or drift by rotation on its own axis under unbalanced frictional forces, such drift being immaterial to its displacement motion but of great practical importance, The motion of the vanes is one of rectilinear reciprocation in planes parallel with their surfaces exposed to the working fluid.

In order to show the range of practical application of the invention, it has been illustrated primarily in the form of a complete rotary power unit comprising a two-cycle rotary internal combustion engine and a rotary oil clutch or coupling through which the power is transmittedirom the engine to the load or from the load tothe engine for braking action.

The invention will be fully understood from the following description, taken in connection with the accompanying drawings, in which latter- Figure 1 is a side elevational view, with parts broken away, of the internal combustion engine and therotary oil clutch, showing the circulation of oil for cooling the engine;

. Fig. 2 is a perspective view of the clutch mechanism, with the clutch disengaged;

Fig. 3 .is a longitudinal sectional view of the clutch mechanism, showing the clutch in its maximum operating position;

Fig. 4 is a transverse sectional along the line IV--IV of Fig. 3;

Fig. v5 is a transverse sectional alone the line V-V of Fig. 3;

Fig. 6 is a transverse sectional along the line VI-VI of Fig. 3;

Fig, 7 is a transverse sectional along the line VII-VII of Fig. 3;

Fig. 8 is a detailed side elevational View showing the clutch shaft and associated parts in position non-operative for thetransmission of power;

Fig. 9 is a transverse sectional View taken along the line IX-IX of Fig. 8;

Fig. 10 is a transverse sectional view taken along the line X-X of Fig. 8;

Fig. 11 is a transverse sectional View taken along the line XI-XI of Fig. 8;

, Fig.12 is a fragmentary transverse sectional view through the clutch casing, showing in side view taken view taken view taken view taken elevation the relative position of the rotors and vanes when the rotors are passed to a position beyond that illustrated in Fig. 4;

Fig, 13 is a side View taken along the line XIII-XIII of Fig. 12;

Fig. 14 is 'a view similar to Fig. 12 when the rotors have passed to a position beyond that shown in Fig. 4; and

filed application Ser. No. 650,018, entitled Rotary engine, filed January 3, 1933 now U. S. Patent No. 2,112,844, issued April 5,1938. Reference is also made to my application SenNo. 683,593, filed August 4, 1933, which matured into U. S. Patent No. 2,037,619 on July 20, 1937 for an illustration of the clutch mechanism.

Referring more particularly to Fig. 1 of the drawings, there is illustrated a two-cycle rotary internal combustion engine designated A, equipped with integral blowers designated B, a rotary compressor designated C taking a small proportion of highly carburetted air from a carburation system (not shown) and delivering it under pressure to the engine A, an oil circulating pump E receiving the lubricating and cooling oil scavenged from the engine through conduit [0 and delivering the same under pressure through a conduit "53 to a rotary oil clutch F which serves also by virtue of its rotation in free air as an oil cooler, thence to the crank shaft of the engine back to the engine Thus the engine oil is used for both lubricating and cooling and power transmission.

The engine construction comprises a crank shaft designated I5 which is a single throw.

. posed faces of the cheeks of the crank throws of the shaft have grooves I6 turned in them surrounding the crank pin and communicating with bores I1 through the counterweights. These grooves and radially inclined bores serve as centrifugal pumps to collect and discharge the oil fed in through the bore 20 of the crank shaft. Radial flanges I9 fixed to the outer faces of the counterweights and crank throws act as the impellers ofcentrifugal scavenging pumps, as will later appear. A radial discharge nozzle 2| for cooling oil, removably attached to the center of the crank pin and communicating with its bore through radial ports, completes the crank shaft assembly. The rotor 22 of the engine is in the form of a hollow cylinder with hubs 7a and 12) extending the length-of the crankpin I8 and constituting the crankcase. The interior of the rotor 22 is hollow, constituting an annular recess at 22a.

The rotor is internally cooled by lubricating oil supplied by the nozzle 2|, Special provision must be made to effect satisfactory cooling with this medium. The requirement to be met is that oil must be supplied at an adequate rate to limit the average temperature'rise, and that there must :be high velocity turbulent circulation over the surfaces to be cooled. The first requirement is met by providing a circulating pump E of adequate capacity and appropriately large delivery passages. The second requirement is met by extending the delivery nozzle -2I out to the inner periphery of the annular recess 22a of the rotor, .as'shown in Fig. '1, and by making it wide enough to 'act as an effective impeller. Since this nozzle is fastened to, and rotates with, the crank shaft, while the rotor itself has no definite motion of rotation with respect :to the casing, the nozzle acts as an impeller to circulate the entire body v.of oil around within the rotor at crank shaft speed.

The incoming fresh oil discharged from the fluid clutch by 'way of the communicating bore 20 in the engine crankshaft and the nozzle .ZI is delivered at the periphery by the nozzle 2I under pump pressure and forced out at the center through "the grooves in the outer faces of .the bearmg bushings of the rotor pump. Centrifugal force plays no partin the supply of the cooling oil or its internal circulation, both being positive displacement actions varying directly with engine speed. Centrifugal action is relied upon, however, to remove the oil from the collecting grooves I6 at a rate in excess of its supply to prevent the building up of a pressure in these grooves and also for scavenging the compartments in the end casings 23 into which the oil'collects.

When using the rotary power unit for automotive vehicles the fluid clutch permits of indefinitely extended controllable slippage with full and continuous torque. This in turn permits of the substitution of an emergency low speed and a reverse gear for the variable speed transmissions now employed in automobiles, the increase of driving torque and higher motor speeds gained from such transmissions being not required with the rotary engine. The permissible rotation speed of the latter, as well as its torque, is so high that under its normal or direct drive gear ratio, it delivers the maximum torque required for ordinary starting acceleration and hill climbing.

In Figs. 2 and 3, the rotary clutch or casing is shown as an individual unit. The casing thereof, designated I35, is the driving member in ordinary service, although the mechanism is fully reversible. The driven member is a shaft I39 passing through a stuffing box and bearing in one end of the casing and having a pilot hearing in the other end of the casing. Within the casing the shaft is divided, each end carrying a T-head M9, the two heads being joined by crank pins in the form of inclined splined bars I4I which lie in offset planes on either side of and parallel with an axial plane of the shaft. The twin rotors or cylindrical pistons I42 are formed .as annular ball bearings, the inner race of each being carried by one of the bars I H which passes through an inclined splined hole therein. Each inner race is cut out on one side as shown at I43 to clear the bar on which the other race is mounted. Each of the rotors operates in a separate chamber of the casing, the two chambers being separated by a common wall I44. This Wall, as well as the outer face walls I00 of the chambers, has leakage grooves I 15 milled in its surface, the grooves being of maximum depth and width at the inner ends and tapering to points at the outer ends. The leakage grooves I45 are of substantially V-shape, increasing in width and depth toward the center of the chambers. The outer ends lie on a circle of about the mean radius of the chamber, leaving the outer portion .of the chamber Walls unaflected.

Each working chamber comprising an annular wall Jill and side walls I44 and I00 is subdivided into compartments by vanes I46 sliding in cylinders I47 which also house compression springs I48 which hold the contact shoes I 49 in contact with the rotor surface. The vanes are hollow and are vented .on one side as shown at I50 to open into the working chamber on that side. Each of the two rotary units has six vanes. The two sets of vanes may coincide angularly for easy balancing, or may be staggered, the latter construction being here shown for clarity. The cylinders l l'i have beendesignated a to ,f in Figs. 12 and -14.

For admission of the working fluid to the working chambers the latter have liberal inlet ports I5I (see .Fig. 4) in their outer side faces. The crankcase is formed by the Walls I05, I06 and I51. The fluid is supplied from the crankcase to the ports I5I through passages I II! in the wall I06 and automatic inlet valves I52 carried in cages I52 which are held in the wall I06 of the casing by closure plugs I 53, the valves I52 designed to be unaffected by centrifugal force, the seat lying in the radial line of the pivot. From valves I52 the fiuid flows through passages 20I to the working chambers. In the general View, the inlet valves have been illustrated as simple gate valves moving in a line parallel with the axis of rotation.

A ball valve construction is illustrated in connection with the outlet valves I54. The latter prevent inflow through the outlet or relief ports I55 and passage I I2 which communicate with the top or areuate wall IOI of each working chamber and by appropriate passages I55a and ducts 9 in the casing with a groove I56 formed by the annular wall I51a surrounding the shaft I39. The portion of the shaft adjacent this groove has radial ports I 56a opening into a central bore I51 drilled in from the T-head of the shaft and thus opening to the crankcase. To control flow of oil from the outlet ports to the crankcase through the ducts described, there is provided a plunger valve I58 fitting the bore I51 and having a'stem I58a which passes outward through the shaft I39 to a point of attachment to a T-head I59 sliding in a slot through the shaft. The outer prongs I59a of the T-head I59 are loosely engaged between the races of a ball thrust bearing I60 which is operable by a ring I6I with which the clutch operating yoke, not shown, is connected.

It will be clearly seen from the above description with reference to Figs. 2 and 3, that the driving shaft is the shaft I atthe left hand end of Fig. 3. This shaft is keyed to the casing or housing I 38 and turns with it as one piece. The driven shaft I39 comprises a journal having a bearing in the driving shaft, T-heads I40 connected by splined members MI, and the straight length of shaft to the right of these. 7

The twin rotors I42 turn with the driven shaft I39 at an eccentricity depending. on the horizontal position of the driven shaft I39. The twin rotors run on ball bearings, the inner races being formed in the circumference of the rotors and the outer races in rings which are held against the shoes I49 of the vanes I46 by spring concontact. One possible motion of a ring is that with the driving shaft fixed and only the driven shaft rotating, every point in it revolves in a circle of radius equal to the eccentricity. This is slightly modified by shifting or drifting of the ring on its own center. This latter motion is entirely accidental and free from positive constraint, but it in no way affects the periodic expansion and contraction in a cross sectional plane, as shown in Fig. 4, of the spaces between the vanes, the casing I 38, and the ring.

The clutch is normally held in the fully engaged position shown in Fig. 3 by spring I62 bearing at one end against the casing and at the other against a thrust collar I62a and bearing on the shaft I39. Fluid may be supplied continuously to and through the clutch casing by a pipe I63 which enters a hollow gland I64 riding on a boss on the face of the casing and communicating with the crankcase through the ducts 200 shown. From the crankcase the fluid may be discharged through a bore in the driving shaft as described in connection with Fig. 1. It will be understood, however, that if the casing be initially filled with oil or other liquid, no continuous supply or discharge is required for operation of the clutch, and the pipe I63 and gland I64 may be omitted in such cases, the cluth with its initial filling being a complete self-contained unit.

The operation of the clutch is as follows: The rotors I42 are in their position of extreme eccentricity in Fig. 3. In this position, the maximum driving force is transmitted from the driving shaft I5 through the fluid in the working chambers to the driven shaft I39 since the fluid is considered to be an imcompressible fluid. In this position, the T-head I40 is in substantial en- I gagement with the right hand wall of the casing I38. Escape of the fluid from the working chambers is prevented by means of the plunger valve I58 which is in the position as shown in Fig. 3, to block the ports I56a.

The clutch can be disengaged by moving the rotors to their concentric position illustrated in Fig. 2, as will now be described. The ring I6I controls the position of the plunger valve I58 by means of rod I58a. The ring I6I is moved to the left as viewed in Fig. 3, to the position shown in Fig. 2, in which the plunger valve which is of hollow construction is disposed to the left of the ports I56a to permit free passage of the trapped fluid from the working chambers through the passages II2, I'55a, ports I56a and bore I51, into the crankcase of the clutch. The ring I62a which controls the longitudinal position of the driven shaft I39 is now moved to the left as viewed in Fig. 3, until the T--head I40 substantially abuts against the left hand wall I05 of the casing I38. This is the position illustrated in Fig. 2. Passage of the bars I4I through the inclined holes of the rotors I42 has retracted the rotors to their concentric position. Additional escape of fluid from the working chambers to facilitate the shifting of the position of the rotors is facilitated by the leakage grooves I45p-rovided in the walls of the working chambers.

To shift now from the concentric position of the rotors I42 illustrated in Fig. 2, to the extreme eccentric position of the rotors illustrated in Fig. 3,. and assuming that the plunger valve I58 is still in its position to the left of the ports I560; to permit free flow of fluid from the working chambers, the spring is permitted to press the collar I62a to the right, as viewed in Figs. 2 and 3. The pressure of the spring I62 moves the driven shaft I39 to the right until the T-head I40 is in substantial abutment against the right hand wall of the chamber I38. This movement of the driven shaft I39, with the bars I4I aflixed thereto, moves the rotors I42 outward to the extreme eccentric position illustrated in Fig. 3. The collar I6I is now moved to the right as viewed in Figs. 2 and 3, to the position illustrated in Fig. 3, thereby positioning the plunger valve I58 to cut off escape of the fluid trapped in the working chambers. Full driving force can now be transmitted from the driving shaft and easing I38 through the fluid in the working chambers to the driven shaft I39.

I claim:

1. In a clutch, two shafts co-axial with respect to each other, a casing rigidly secured to the first shaft and encircling the adjoining end of the second shaft, an annular chamber in the casing, a cylindrical piston secured to the second shaft contacting with the side and end walls of the chamber, movable mechanism cooperating with the piston to divide the chamber circumferentially into compartments, means for varying the radial position of the piston with respect to the second shaft, the compartments adapted to contain fluid whereby rotation of the casing transmits torque to the piston through the fluid when the piston is in off-centered position, and V-shaped grooves in the side Walls of the annular chamber extending radially outwardly from the base of the annular chamber increasing in width and depth toward the center of the chamber to permit of controlled leakage of the oil from the chambe -V 2. In a clutch, two shafts co-axial with respect to each other, a casing rigidly secured to the first shaft and encircling the adjoining end of the second shaft, an annular chamber in the casing, a cylindrical piston secured to the second shaft contacting with the side and end walls of the chamber, movable mechanism Cooperating with the piston to divide the chamber circumferentially into compartments, passageways leading from the casing to the compartments and containing a one-way valve to permit one-way passage of the fluid from the casing to the compartments, a discharge passageway leading from each compartment to a single bore leading to the casing, and a manually controlled valve in the bore operative to close the flow of fluid from the compartments into the casing whereby rotation of the casing transmits torque to the piston through the fluid when the piston is in off-centered position.

3. In a fluid clutch, two shafts coaxial with respect to each other, a casing adapted to contain fluid rigidly secured to the first shaft and encircling the adjoining end of the second shaft, an annular chamber in the casing, a cylindrical piston contacting with the side and end walls of the chamber, means for dividing the chamber circumferentially into compartments, a bar secured to the second shaft inclined to the longitudinal axis of the shaft and slidably engaging a hole in the piston whereby longitudinal movement of the second shaft effects radial movement of the piston, inlet passageways leading from the casing,

to the compartments, a discharge passageway leading from each compartment to a single bore leading to the casing, and a valve in the bore operative to open the flow of fluid from the compartments into the casing whereby radial move ment of the piston is permitted.

4. In a fluid clutch for transmitting power between a casing and a shaft, a casing encircling the adjoining end of the shaft, an annular chamher in the casing, a cylindrical piston contacting with the side and end walls of the chamber, means for dividing the chamber circumferentially into compartments, inlet passageways leading from the casing to the compartments, a discharge passageway leading from each compartment to at single bore leading to the casing, a valve in the bore operative to open the flow of fluid from the compartments into the casing whereby radial movement of the piston is permitted, and means for effecting radial movement of the piston.

5. A fluid clutch according to claim 3 in which a one-way valve is disposed in each inlet passageway and discharge passageway to permit one-way passage of the fluid from the casing to the compartments and from the compartments to the single bore.

6. In a fluid clutch, a casing encircling the adjoining end of a shaft, annular chambers in the casing, a cylindrical piston contacting with the side and end walls of each chamber, means for dividing each chamber circumferentially into compartments, diagonally crossing bars integral with the shaft each slidably engaging a hole in one of the pistons whereby longitudinal movement of the shaft eifects opposite radial movement of the pistons, inlet passageways leading from the casing to the compartments, a discharge passageway leading from each compartment to a single bore leading to the casing, and a valve in the bore operative to open the flow of fluid from the compartments into the casing whereby radial movement of the pistons is permitted.

FRANK A. HOWARD. 

